Modern techniques of investigations - magnetic resonance imaging and spectroscopy - based on nuclear magnetic resonance phenomenon, can have a decisive meaning in case of diagnostic difficulties. Recently, NMR Spectroscopy is of great importance, especially in examinations differentiating benign and malignant tumors. We describe course of the disease and diagnostic difficulties noted in patient suffering of lymph nodes' cancer (Hodgkin's disease) with coexistent systematic vasculitis which involved kidneys, peripheral vessels and probably brain vessels. During complete remission of the Hodgkin's disease and in stable stage of systematic disease developed neurological symptoms sugesting brain tumor. We consider the possibility of brain tissue infiltrations, resulted from Hodgkin's disease, the presence of tumor of another ethiology or thrombotic-embolic abnormalities in the course of vasculitis. Diagnosis was made taking into considerations not only the sole clinical and biochemical manifestations of coexisent diseases, but first of all NMR images, pointing at presence of muliple ischemic foci. Univocal NMR images in vivo and normal parameters of 31P NMR spectra during neurological episodes allowed for diagnosis of systemic disease progression, not this of neoplastic origin. The resonance peaks from phospholipides started to be distinguishably lower - what characterizes malignancy - only after the relapse of Hodgkin's disease. These was confirmed by histopathological examination. We assume that in presence of essential diagnostic difficulties, especially due to differentiation between malignant and non-malignant diseases, both MR imaging in vivo and 31P NMR spectroscopy are of extreme importance. Moreover, we would like to stress the prognostic value of 31P NMR spectra - their normal values were noted three months prior to the confirmation of CR by means of traditional methods.

Keywords: 31P NMR spectroscopy, MRI, diagnostic difficulties